Unit of Assessment

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Summary of the impact

The zebra mussel is one of the world's most economically and ecologically
important pests, but existing control approaches cause significant
deleterious environmental effects. Researchers at the University of
Cambridge have developed a `BioBullet' against zebra mussels, which
encapsulates toxins in a harmless edible coat, enabling efficient,
targeted product delivery and dramatically reducing environmental
pollution. [text removed for publication] Further successful formulations
are being developed by the researchers and the company for fouling in
shrimp farms and enhancing shellfish aquaculture.

Underpinning research

For the past 12 years, the Aquatic Ecology Group (AEG) in the Department
of Zoology has been studying the biology and rapid spread of the zebra
mussel, Dreissena polymorpha. One of the world's most economically
and ecologically important pests, control of zebra mussels now costs an
estimated U.S.$5 billion per year in North America, due to its ability to
block the raw water cooling systems of power stations and water treatment
works.

Led by Dr David Aldridge (Affiliated Lecturer 1997-present), the AEG
initially mapped the location and spread of zebra mussel populations in
Britain1, documenting a recent, rapid increase in both
abundance and distribution, coupled with deleterious ecological impacts
(increased water clarity, changes in community composition, declines in
native mussel populations).

Although chlorination is a widespread and licensed control technique, it
is non-specific; application in an open ecosystem therefore has
devastating effects on non-target species. Also, zebra mussels can sense
chlorine and other toxins in the environment and respond by closing their
valves; effective treatment therefore requires prolonged dosing. However,
prolonged chlorine dosing in raw water produces trihalomethanes by
reaction with organic material; these are toxic to both humans and other
animals, restricting the doses that can be applied. As a result, there has
been continued tightening of regulatory controls on the discharge of
chlorine into the environment (e.g. the European Water Framework Directive
2000/60/EC).

Dr Aldridge, in collaboration with Dr Geoff Moggridge (Department of
Chemical Engineering and Biotechnology), theorised that toxins could be
delivered to zebra mussels in an edible coating, overcoming the valve
closure response, and requiring smaller doses to be effective. An umbrella
patent, providing broad IP protection for the encapsulation of any
material for delivery to filter feeders, was granted to Aldridge and
Moggridge in Europe in 2003 and in the US in 2008. Commercial development
was supported by winning the first BBSRC Bioscience Business Plan
Competition, with `BioBullets Limited' founded by Aldridge and Moggridge
as an independent company in 2000. In February 2001, Aldridge and
Moggridge, via BioBullets Ltd., began a collaboration with Anglian Water
to better understand the effect of encapsulated products on zebra mussels,
and in 2003, a DTi SMART Award enabled various coating formulations to be
tested [text removed for publication].

Whilst refining the capsule, the AEG also determined which toxin should
form the core of the `BioBullet'. They initially chose potassium chloride
(KCl), having demonstrated that it is particularly toxic to freshwater
bivalves [text removed for publication], but at low doses is inert to most
other organisms2. The mussels' natural filtering behaviour
internally concentrates the toxin, reducing the quantity of active
ingredient required, and it is effective as a one-off treatment, rather
than needing continuous dosing.

Further academic work by the AEG demonstrated that zebra mussels show
seasonal peaks of increased susceptibility to toxins3, which
has implications for the overall design of chemical control strategies,
and for the amount of toxin that needs to be released into a water system
to achieve the desired effect. Subsequent studies to understand the
filter-feeding behaviour of zebra mussels have identified methodologies
for indirectly quantifying fouling levels in inaccessible pipelines, and
demonstrating the potential of mussels as bioremediation tools within
nutrient-enriched reservoirs4. Additional studies by the group
demonstrated that multiple active agents, with differing physiological
impacts on zebra mussels, can have synergistic effects, thereby reducing
the amount of product needed to control pest species5.

Details of the impact

Impacts on production: decisions by regulatory authorities have been
influenced by research
In December 2008, the GB Drinking Water Inspectorate (DWI) approved the
BioBullets product Silver Bullets 1000 for use in public water supplies
[text removed for publication]. A second formulation suitable for very
large water volumes and carrying a different active ingredient (currently
confidential), Silver Bullets 2000, was approved in April 2011 [text
removed for publication]. These approvals demonstrated the environmental
safety of the products, and enabled them to be tested within operational
drinking water plants. The Environment Agency has also provided permits
for discharge of Biobullets' products into recipient streams and rivers,
with monitoring of riverine biota before and after dosing trials
repeatedly showing the broken-down product to have no measurable impact on
aquatic biota8, and regards "The biobullet formulation [as]
an essential management tool in our response to a variety of priority
invasive non-native species."8

Impacts on production: costs of [drinking water] production have been
reduced
Since the 2008 DWI approval, eight full-scale trials have been conducted
within the impact period in seven UK waterworks, belonging to Anglian
Water9, South Staffordshire Water10, Thames Water11,
Severn Trent Water and Welsh Water. Dosing of Silver Bullets 1000 [text
removed for publication] has yielded highly successful results [text
removed for publication]. Removal of mussels from raw water pipes has
resulted in reduced pipe restrictions, with related savings on pumping
costs. For example, a representative of Anglian Water said: "There had
been a significant loss of performance at our water treatment works in
Covenham due to large numbers of zebra mussels blocking the pipes
feeding the plant. Use of BioBullets significantly reduced the number of
mussels, demonstrating a cost effective solution to the problem".9

The potential financial impact of BioBullets' products on the UK water
industry is very significant and has already been recognised. For example,
Thames Water spent £1m in 2010 alone clearing zebra mussels from their raw
water pipes11. Anglian Water reported in 2011 that the
increased pressure required to pump water through zebra mussel-infested
pipes is costing them £500K per annum in additional energy costs11.
Following trials of BioBullets, the companies stated:

"We believe BioBullets will save hundreds of thousands of pounds in
operational costs in a way that has no adverse impact on the
environment."11

We are very hopeful BioBullets are the solution we've been looking
for having trialed them at our treatment works at Alton in Suffolk and
Pitsford in Northamptonshire. In both cases we saw a significant
reduction in the numbers of mussels without any impact on the
treatment process or the environment."11

Currently, BioBullets is currently negotiating commercial terms with a
service provider [text removed for publication] to deliver the product
across the UK water industry.

Impacts on commerce: the performance of an existing business has been
improved; industry has invested in research and development
In June 2011, a dedicated manufacturing plant for BioBullets was opened in
Bristol [text removed for publication]. The plant was part funded through
a £500K grant from the Technology Strategy Board [text removed for
publication]. The plant has an annual capacity of 5000 tonnes [text
removed for publication].

International impacts on commerce
Tests and trials have been carried out in other countries: tests in the
Netherlands (by [text removed for publication] a major consultant to the
European and Asian power industries) yielded 100% mortality[text removed for publication].
Trials funded by the Aragon government in Spain in
February 2011 resulted in a highly effective removal of fouling zebra
mussels and Asian clams (Corbicula spp.) within irrigation systems:
"Infestation of irrigation systems by zebra mussels and Asian clams has
presented farmers with problems in maintaining adequate water supplies
to crops. BioBullets was able to remove substantial volumes of mussels
from the irrigation pipes."13 BioBullets is currently in
discussion with both the US and Spanish water industries about using their
products to control zebra mussels in water supplies in those countries.

Given the breadth of the initial patent, the company has diversified its
product range to target a broad range of invasive aquatic species. In
2006, BioBullets started development and testing of a formulation to
control fouling by invasive bivalves (Mytilopsis and Perna
spp.) in [text removed for publication] shrimp farms. In laboratory tests
in [text removed for publication] in 2010, one formulation yielded 100%
mortality in mussels, but with no harmful effect on the shrimps.
Discussions are underway between BioBullets and [text removed for
publication] two [text removed for publication] shrimp farming companies
[text removed for publication] for full-scale field trials. In 2008 a
grant to BioBullets from the US National Oceanic and Atmospheric
Administration (NOAA)14 enabled the development and testing of
a formulation to control invasive seasquirts (Didemnum vexillum),
pests which threaten the global marine aquaculture industry. Trials of
formulations in New Zealand in 2010 produced high mortalities in both Didemnum,
and a second invasive and economically damaging seasquirt, Ciona clava15.

The underpinning BioBullets technology has become a platform for
expansion of the company into other areas. A Feasibility Grant from the
TSB in 2011 enabled development [text removed for publication] to enhance
the growth rates and survival of commercial shellfish larvae.16
[text removed for publication]. In January 2013, BioBullets led a
consortium of three SMEs (the others being Micropore Technologies, UK, and
Scalpro, Norway) in successfully bidding for Eureka Eurostars funding (an
EU R&D programme) to develop microencapsulated feed products to
enhance commercial shellfish yields.17 The speed of juvenile
shellfish growth is currently constrained by the availability of, and
nutrient level in, algal cells; BioBullets' platform technology is
enabling them to encapsulate tailored and optimised nutrient packages for
different shellfish species.

Impacts on the environment: the management of an environmental hazard
has changed
The adoption of Biobullets by UK water companies has changed how the
industry approaches control of zebra mussels. The products are reducing
the use of chlorine in water supplies on a global scale, and so reducing a
major human and animal aquatic toxin: "Biobullet provides a unique
formulation that has the potential to allow us to target a variety of
invasive non-native species in a manner that will protect the rest of
the ecology from non-target damage."8

Since 2004 research and grant writing has been led by David Aldridge, in
his role as Managing Director of BioBullets Ltd. Grant funding has enabled
part-time employment of Aldridge and one other person as consultants to
the company. [text removed for publication] BioBullets Limited is expected
to become commercial in 2014.

Sources to corroborate the impact

DWI regulatory approval for Silver Bullets 1000

DWI regulatory approval for Silver Bullets 2000

Personal communication to Aldridge from the Senior Technical Advisor on
Invasive Species for the Environment Agency

"BioBullets for the Control of Fouling Sea Squirts" - US National
Oceanic and Atmospheric Administration: US$120,000 Ref. 51710002423,
2008-2009: David Aldridge (PI, via BioBullets Ltd.)

Laing, I., J. Bussell, et al. (2010). Assessment of the impacts
of Didemnum vexillum and options for the management of the species
in England. Fera, CEFAS and Natural England: 62. p36
[text removed for publication]